Process for sweetening baked comestible and product produced thereby

ABSTRACT

Comestibles, such as baked goods and cereal products, are sweetened by application of an aqueous solution of at least one L-aspartic acid sweetening derivative to provide products which exhibit a uniform sweetening response when eaten, i.e., they are substantially free of &#34;hot spots&#34;. The sweetening derivative is absorbed into the comestible to obtain products which do not have a sugar-coated or sugar dusted appearance.

FIELD OF THE INVENTION

The present invention relates to the preparation of baked comestiblessweetened with an L-aspartic acid sweetening derivative. Morespecifically, this invention relates to a process for sweetening cerealproducts and baked goods by applying thereto an aqueous solution of anL-aspartic acid sweetening derivative, and to the product produced bythe process.

BACKGROUND OF THE INVENTION

Various cereal products and baked goods are sweetened during preparationeither by incorporating a sweetening ingredient in the starting mixprior to baking, or by applying a sweetening composition to the productafter it has been baked. In the past, the sweetening agent generallyemployed for such purposes has been a nutritive carbohydrate sweetener,such as sucrose, fructose, corn syrup and the like. More recently,efforts have been made to replace the aforesaid carbohydrate sweetenersin baked comestibles due to concern over the effect of such sweetenersupon diet and dental health. Among the substitute sweetening agentsproposed have been L-aspartic acid sweetening derivatives, particularlythe dipeptide N-L-α-aspartyl-L-phenylalanine methyl ester (aspartame).

The L-aspartic acid sweetening derivatives are potent sweetening agents,reportedly being, gram-for-gram, 100 to 200 times as sweet as sucrose.The intense sweetness produced by these compounds results in negligiblecalories when used at isosweet levels in place of sucrose. Similarly,the L-aspartic acid derivatives generally possess negligiblecariogenicity.

The L-aspartic acid sweetening derivatives are known to be moisturesensitive, in that they contain an ester linkage that may hydrolyze to adipeptide, which, in turn, may cyclize to the correspondingdiketopiperazine (DKP), with a corresponding loss of sweetness. However,relatively stable solutions of these compounds may be prepared undercontrolled conditions of temperature and pH. An aqueous solution ofaspartame, for example, has maximum stability at ambient temperature ata pH of about 4.3. Aspartame exhibits a maximum water solubility,(approximately 10 gm/100 ml at 20° C.) at a pH of 2.2 and a minimumsolubility (approximately 1.0 gm/100 ml at 20° C.) at a pH of 5.2, itsisoelectric point. Solubility increases with temperature increase.

The L-aspartic acid sweetening derivatives also tend to decompose to DKPat elevated temperature, with attendant loss of sweetness.

As a result of the heat instability problem a number of processes havebeen proposed in which a coating composition comprising the L-asparticacid sweetening derivative is applied to the surface of the alreadybaked comestible to reduce exposure of the sweetening derivative toelevated temperature over an extended period. However, because of themoisture sensitivity and relatively low solubility of the L-asparticacid sweetening derivatives, the use of aqueous solutions thereof as asweetening composition has been avoided. Incomplete solution of theL-aspartic acid sweetening derivatives tends to result in non-uniformsweetening in topical applications of such sweetening derivatives to theexterior of a baked comestible. Non-uniformity of application of thesesweetening derivatives is a concern because of the production of "hotspots", which is an expression used by those experienced in the art torefer to a non-uniform sweetening response attributable to highconcentrations of the sweetener at discrete locations on the foodstuff.

Various procedures have been suggested for applying L-aspartic acidderivative-containing sweetening compositions to baked comestibles, soas to overcome the moisture sensitivity and ameliorate the adverseeffect produced by low solubility of these sweetening derivatives.Included among the suggested procedures have been several which involveencapsulating or coating particles of the L-aspartic acid derivativewith edible coating materials followed by drying and granulation.

In U.S. Pat. No. 3,962,468, particles of L-aspartic acid derivatives arestabilized in a dry fixation by causing a slurry-forming level ofundissolved hydrated particles of the sweetening agent to be dispersedin an aqueous dextrin solution as discretely distributed, undissolvedparticles, and drying the dispersion to encapsulate the particles of theL-aspartic acid derivative in the dextrin.

In U.S. Pat. No. 4,004,039, aspartame crystals are stabilized into aparticulate form so as to be freeflowing with other powdered materials.The stabilization process involves admixing the crystals with amatrix-forming material such as dried coffee extract, whey, low dextroseequivalent starch polymers and protein extracts, heating the admixtureto form a melt, in which the ester crystals are discretely distributed,calendering the melt between two rollers to submerge the crystals in themelt, cooling the same, and then granulating the products to produceparticles which encapsulate the crystals distributed therein.

In U.S. Pat. No. 3,934,048, dipeptide sweeteners, including aspartame,are provided with a satisfactory rate of solubility and storagestability due to low hygroscopicity, by co-drying a solution of thedipeptide and an edible, bland, low-calorie polysaccharide.

Encapsulating or coating L-aspartic acid sweetening derivatives in theabove manner, purportedly has the advantage of providing a comestiblehaving the sweetening derivative in a relatively low hygroscopic statethat achieves sweetness uniformity.

An approach to coating comestibles such as cereal products, baked goodsand confectionary foodstuffs with an L-aspartic acid derivativecontaining-coating which attempts to minimize the above-noted problemscaused by the thermal instability and low solubility of such sweeteningderivatives is described in U.S. Pat. No. 3,955,000. In that process,the L-aspartic acid derivatives are admixed in aqueous suspension with astarch hydrolyzate comprising predominantly oligosaccharide solidshaving a low dextrose equivalency, of about less than 30, and applied asa coating solution to the comestible. The coating of the dried solution,it is disclosed, smoothes out the taste impact generated by anysweetening imbalance attributable to the incomplete solution of thesweetening derivative, or non-uniformity of its dispersion. The uniformdistribution of sweetness, and attendant minimizing of "hot spots" whenthe food is eaten, is attributed principally to the starch hydrolyzate.

The coating solution used in the process of U.S. Pat. No. 3,955,000 ismaintained at a temperature below 200° F. so as to have the L-asparticacid derivative dispersed therein as undissolved hydrated particles. Thesolution is applied to the foodstuff by atomization or other spraytechniques. The coated comestible, it is disclosed, is dried at producttemperatures which do not exceed 200° F. in order to assure that thesweetening agent is not degraded. The coated comestible is dried to astable moisture content of below about 8%.

The coating process of U.S. Pat. No. 3,955,000 produces a frosted orglazed product that has a sugar-coated appearance. Other substances,such as fat and starches, it is disclosed, can be incorporated in thecoating to create a dull or crystalline appearance suggestive of othersweetened cereal applications. However, the appearance of a sugarcoating, whether glazed or dull, is associated with an undesirableamount of sugar by many consumers. Further, the dextrins, and otheradditives in the coating, increase the calorific value of the foodstuff.

Still another prior art attempt to prepare comestibles having anL-aspartic acid derivative containing-coating is described in U.S. Pat.No. 4,378,377. The process involves preparing a coating compositioncomprising the sweetening derivative and hydrolyzed or unhydrolyzedvegetable protein isolates in an aqueous suspension, "enrobing" thecomestible with the coating composition in an amount sufficient toprovide the desired level of sweetness, and drying the coated comestibleto a final moisture content of less than about 5.0%. The aqueoussuspension essentially comprises, by weight, from about 0.1% to 4.0%sweetening derivative and from about 1% to about 30% vegetable protein.The weight ratio of aqueous suspension to comestible base may varydepending on the level of sweetness desired in the coating and theconcentration of the sweetening derivative in the aqueous suspension. Ingeneral, the weight ratio of aqueous suspension of comestible base mayrange from about 1:12 to about 1:1.3, a weight ratio in the range fromabout 1:9 to about 1:3 being preferred. The enrobing step is generallypracticed at a temperature of from about 50° F. to 100° F. for both thecomestible base and the aqueous suspension. Any conventional enrobingtechnique may be employed, such as tumbling or spraying.

The proteinaceous suspending agents function to maintain the sweeteningderivative in suspension, (i.e. a large fraction of the sweetener willnot be dissolved, but will be suspended and dispersed), to bind thesweetening derivative to the surface of the comestible, and to aid inthe even distribution of the suspension over the comestible base duringenrobing. The use of the L-aspartic acid sweetening derivative and thevegetable protein isolates in combination, it is disclosed, has theadvantage of permitting the use of ambient temperature or "cold water"aqueous suspensions in preparing coated comestibles, thereby minimizingthermal degradation of the sweetening derivative and attendance loss ofsweetness.

The finished sweetened product, it is disclosed, has a sweetness profilesimilar to sucrose-sweetened comestibles and desirably comprises fromabout 0.05% to 0.4% of sweetening derivative and from about 1% to 20% ofvegetable protein (dry weight). However, comestibles produced accordingto the process of U.S. Pat. No. 4,378,377 also have the appearance ofhaving a sugar-coating which, as noted above, is associated with anexcessive sugar content by many consumers. Moreover, the vegetableprotein isolates used to provide the coating, such as soy proteinisolates, often produce a slightly bitter aftertaste.

The process for sweetening baked comestibles according to the presentinvention provides an acceptable level of sweetness in the finalproducts without providing a sugar coated appearance. The processenables the sweetening of natural products, such as shredded wheat,while retaining their natural appearance. The sweetening derivative isuniformily applied to the comestible, so that the occurrence of "hotspots" is at least substantially avoided. In practicing the presentinvention, it is unnecessary to encapsulate the sweetening derivative orincorporate a carrier or fixative therewith in order to prevent moisturedegradation and consequential loss of sweetness. It is believed that thesweetening derivative is absorbed into the body of the foodstuff, andthereby protected from the deleterious effects of moisture, as opposedto remaining on the surface thereof where it may more readily undergodecomposition. Further, because the sweetening process of this inventionrequires no carrier or fixative, which generally are substances ofrelatively high viscosity, it is easier to operate than a processinvolving the application of a coating composition containing suchadditives. A decided advantage of the process of this invention is thatminimal, if any, drying or heating of the sweetened baked comestible isrequired. Thus, unlike some of the prior art coating processes describedabove, in which drying at elevated temperature is an essential processstep, the present invention involves no risk of thermal degradation ofthe L-aspartic acid sweetening derivative incorporated in the finalproduct.

The products produced by the process of this invention are comestibles,such as cereal products and baked goods which have an L-aspartic acidsweetening derivative uniformily applied thereto, and exhibit a uniformsweetening response when eaten, but which do not have a sugar-coatedappearance. These products also possess excellent shelf-stability.

The present invention is effective for sweetening a variety ofcomestibles with an L-aspartic acid sweetening derivative whileretaining a natural product appearance. It is considerably moreeconomical than the encapsulating, coating, or enrobing processesproposed heretofore.

SUMMARY OF THE INVENTION

The present invention is directed to the preparation of dry, bakedcomestibles that are sweetened by the application of a stabilizedaqueous sweetening solution containing at least one L-aspartic acidsweetening derivative. The aqueous sweetening solution is stabilized bycontrolling the pH thereof in the range of from about 1.5 to about 4.0.An acid solution of the L-aspartic acid sweetening derivative is used toachieve minimum degradation and maximum solubility of the sweeteningderivative.

The sweetening derivative is substantially uniformly applied to thecomestible and absorbed beneath the surface thereof, thus precluding theappearance of a sugar-coating on the final product. By reason of itsabsorption into the foodstuff, the sweetening derivative is protectedfrom the adverse effects of surface moisture. Moreover, minimal, if any,drying of the foodstuff at elevated temperature is required afterapplication of the sweetening derivative to achieve a shelf stableproduct. Hence, there is little risk of degradation of the sweeteningderivative incorporated in the final product due to the effects ofmoisture or temperature.

The product is baked to a moisture content below the desiredshelf-stable level. The aqueous L-aspartic acid sweetening solution isthen applied to the baked comestible to provide an acceptable level ofsweetness and a shelf-stable moisture content. The initial moisturecontent of the baked comestible should be sufficiently low so thatfurther heating of the product is not necessary. The sweetening solutionis typically applied to comestibles having a moisture content from about0.8% by weight to about 3.5% by weight to assure uniform absorption ofthe sweetening agent into the body of the comestible and to obtain ashelf-stable product without the need for subsequent drying at elevatedtemperatures. The moisture content of the finished sweetened comestibleshould be less than about 8% by weight for a shelf stable water activityof less than about 0.7.

Various comestibles may be sweetened in accordance with the presentinvention. However, it is especially suited for the preparation of asweetened, dry, cereal product having a predetermined shape andthickness with visually apparent open pores on the surface thereof. Thefinal product has a sweetened surface layer that is less than one-halfof its thickness, with the L-aspartic acid sweetening derivativecontained in the pores of the product. The sweetening derivative isconfined to the surface layer and defines the same. The presentinvention is particularly useful for the preparation of shredded,ready-to-eat cereals, because the open porous structure of shreddedcereals facilitates absorption of the sweetening solution. The finalsweetened product has, interiorly of the aforesaid surface layer, a bodyportion of substantially uniform composition, with the surface layercomprising the sweetening derivative and the same composition that makesup the body portion. Shredded cereal products produced in this mannerexhibit a uniform sweetening response when eaten, with no sugar-coatedappearance. The natural appearance traditionally associated with 100%cereal grain cereals is retained when such products are sweetened inaccordance with the present invention.

The present invention may also be used to advantage for sweeteningready-to-eat cereals admixed with dried fruit.

DETAILED DESCRIPTION OF THE INVENTION

The L-aspartic acid sweetening derivative used in the present inventionis preferably N,L-α-aspartyl-L-phenylalanine methyl ester (aspartame),based on its recent approval for use in foods by the Food and DrugAdministration. However, L-aspartic acid sweetening derivatives, such asthose disclosed in U.S. Pat. No. 3,955,000 at column 3, line 63 tocolumn 4, line 35, can also be used in producing sweetened dry bakedcomestibles in accordance with the present invention. Procedures for thepreparation of such sweetening agents are well known to those skilled inthe art. See, for example, U.S. Pat. No. 3,799,918. The aspartic acidsweetening derivative should not be encapsulated so as to facilitatedissolution and avoid a coated or sugar dusted appearance.

The sweetening solution employed in the present invention comprises atleast one L-aspartic acid sweetening derivative dissolved in water. Atleast substantially all of the sweetening derivative should be dissolvedin the water to facilitate spraying. The term "solution", as usedherein, refers to a true solution, i.e. a homogeneous mixture formed bydissolving a solute (the sweetening derivative) in a solvent (water).The sweetening solution may contain other substances such as flavoringagents in solution and/or suspension, as described hereinbelow.

The aqueous solution of the L-aspartic acid sweetening derivative ispreferably prepared by adding the sweetening derivative to a warmaqueous solution of a pharmaceutically acceptable acid, which raises thepH of the acidic solution. Additional acid may then be added to adjustthe pH to a level at which the sweetening derivative exhibits optimalstability and solubility. The pH employed will depend upon the specificL-aspartic acid sweetening derivative or derivatives selected. Theconcentration of the sweetening derivative in the sweetening solution isnormally up to about 10% by weight of the final solution, depending uponthe solubility of the sweetening agent in water.

In the case of aspartame, the preferred concentration is about 0.03% toabout 3.5%, most preferably about 2% by weight of the final solution.Aqueous solutions of aspartame have been found to have optimal stabilityand solubility at a pH of about 1.8 to about 2.3. However, a pH in therange of from about 1.5 to about 4.0 can be used. At a pH of less thanabout 1.5 or greater than about 4.0, the stability of the aspartamedecreases noticeably. Also, at a pH of about 1, an unacceptably sourtaste is imparted to the cereal product. At a pH greater than about 6.0,the solubility of the aspartame decreases to an unsuitable level. Anaqueous aspartame solution for use in the present invention ispreferably prepared by adding aspartame to an acidic solution having apH of about 1 to about 1.5 to raise the pH to about 2.2 to about 2.3.Additional acid may be added to finely adjust the pH within thepreferred pH range of about 1.8 to about 2.3.

The temperature of the water should be sufficiently high to completelydissolve the sweetening derivative and acid, but not so high as toadversely affect the stability of the sweetening derivative. In general,the water temperature should be in the range of from about 40° F. toabout 210° F. In preparing a sweetening solution of aspartame, thetemperature is preferably from about 70° F. to about 160° F., and mostpreferably from about 85° F. to about 115° F. to dissolve the aspartamewithout causing substantial decomposition. By maintaining the sweeteningsolution at temperatures within the above ranges, crystallization of thesweetening derivative from the solution prior to and/or duringapplicaton of the solution to the comestible may be avoided. Hot spotsin the final product are also avoided by preventing crystallization.

The use of a true solution, as opposed to an aqueous suspension ordispersion of the sweetening derivative, facilitates handling byreducing equipment clogging and eliminating the need for any specilizedequipment for handling suspensions or dispersions. In addition, thelower viscosity of the solution, and the larger quantity of solutionemployed for the application of a given amount of sweetener assures therapid attainment of substantially uniform distribution of the sweeteningderivative.

The L-aspartic acid sweetening derivative used in preparing thesweetening solution is preferably in pure form. Ordinarly, thesweetening derivative will completely replace the carbohydrate sweetenercontent of the comestible. Complete replacement is preferred so as toreduce the cariogenicity of the final product to the maximum extentpoassible. However, if desired, the L-aspartic acid sweeteningderivative may be used in combination with other nutritive or artificialsweetening agents, to provide a level of acceptable sweetness.Representative of such sweetening agents are saccharin, acesulfam-K,talin, cyclamates, steboside, fructose, sorbitol, sucrose, glucose, andthe like. However, such added sweeteners often lower the dissolutionrate of the dipeptide sweeteners and/or increase the calorific value ofthe foodstuff unnecessarily.

The preferred pharmaceutically acceptable acids for use in the presentinvention are malic acid and citric acid. However, other knownpharmaceutically acceptable inorganic or organic acids or bufferingsystems which include the acids can also be used provided they do notadversely affect the taste of the baked comestible. The organic acidsare preferred organoleptically over the inorganic acids. Representativeof other suitable organic acids are fumaric acid, adipic acid, tartaricacid and mixtures thereof. Malic acid is particularly preferred becauseit imparts a pleasant taste to the finished product. Representative ofsuitable buffering systems are any of the above organic acids incombination with an alkali metal salt thereof.

The sweetening solution also desirably contains an effective amount of amasking or flavoring agent. The flavoring or masking agent serves tohide any undesirable aftertaste the dipeptide sweetener may have and toenhance the sweetness of the finished product. The amount of flavoringagent added to the sweetening solution may be between about 0.5% andabout 2.5% by weight of the solution. When an amount less than about0.5% is used, the desired effect of the flavoring agent tends to becomelost. When an amount greater than about 2.5% is used the taste of theflavoring agent may become too evident. Suitable flavoring agentsinclude vanilla extract, maple, and fruit flavors, with vanilla beingpreferred. The flavoring agent should not detract from the uncoatedappearance of the final product.

The sweetening solution is conveniently applied to the baked comestibleusing any air-pressure assisted spraying means. Various types ofsuitable equipment are widely used in food processing and are familiarto those skilled in the art. A suitable spray apparatus for this purposeis a JAU-1/4 in. spray nozzle manufactured by Spraying Systems Co. It isdesirable that the sweetening solution be applied to the bakedcomestible as a mist to assure even application of the sweeteningderivative to the comestible. Spraying may be performed upon the topand/or bottom of the baked good.

By applying the sweetening solution in the manner described above to abaked comestible of predetermined shape and thickness with open pores onthe surface thereof, a product is obtained which is characterized byhaving a sweetened surface layer less than one-half of the thickness ofthe comestible, and having contained in the pores an L-aspartic acidsweetening derivative, the sweetening derivative being confined to thesurface layer and defining the same. In other words, the sweeteningderivative penetrates beneath the surface of the comestible only to alimited extent. Thus, the finished product will have a body portion ofsubstantially uniform composition interiorly of the sweetened surfacelayer, with the latter being composed of the sweetening derivative andthe same composition that makes up the body portion.

Absorption of the sweetening solution into the baked comestible isfacilitated if the moisture content of the comestible to which it isapplied is less than about 3.5% by weight of the comestible. Generally,moisture contents as low as about 0.8% by weight can be achieved withoutburning or discoloration of the product. The drier the product is, thegreater is the driving force for absorption of the aqueous sweeteningsolution into the product. This avoids the occurrence of hot spots onthe surface of the product and a sugar coated appearance or a sugardusted appearance.

The final moisture content of the sweetened comestible should be no morethan about 8% by weight of the comestible, to prevent loss of a crisptexture and to prevent reduction in shelf stability. The water activityof the final product should be less than about 0.7, preferably less thanabout 0.6 to provide an extended shelf life of at least several months.The final shelf stable moisture content should be attained with little,if any, application of external heat to avoid decomposition of theaspartame and to reduce processing costs. Thus, preferably thecomestible should be baked to a moisture content sufficiently low sothat application of the aqueous sweetener solution alone provides ashelf stable product with an acceptable level of sweetness attributableto the sweetening derivative.

The aqueous sweetening solution is applied to the baked comestible at arate which provides a level of acceptable sweetness, as determined by aprofessional taste panel, in the finished dried comestible. In the caseof aspartame, for example, an application rate which would provide anaspartame level of about 0.03% to about 0.41% by weight of the finishedproduct provides an acceptable level of sweetness.

Representative of the baked comestibles which can be sweetened inaccordance with the present invention are baked goods, includingcookies, and doughnuts, and cereal products, including ready-to-eatcereals in shredded, flaked, expanded extruded, fried, or other forms.Exemplary of cereal products which can be sweetened in accordance withthe present invention are shredded wheat, corn flakes, puffed wheat,puffed rice, expanded oats, puffed corn, bran flakes, and whole brancereal. Such cereal products are prepared in the usual manner and may beeither toasted or untoasted. The present invention is particularlyuseful for the preparation of cereal products that have a wide openporous structure, wherein the pores are visually apparent, such asshredded wheat.

The process of the present invention is of particular advantage insweetening ready-to-eat cereals admixed with dehydrated fruit, such asraisins, currants, blueberries, strawberries, dates, figs, apples, orbananas, or nuts. The problems involved in preparing a mixture ofready-to-eat cereal and dried fruit in which the fruit component hassatisfactory texture and flavor are well known. If the fruit isdehydrated sufficiently to prevent spoilage, the texture of the driedfruit is unappetizingly tough, and unacceptable to much of the consumingpublic. On the other hand, if the fruit is only dehydrated to the extentit retains a high degree of moisture in order to have a soft texture:(1) it will either not be bacteriologically stable at room temperatureor, (2) it will lose moisture to the dry cereal, causing the cereal tobecome soggy with the fruit becoming dry, hard, and excessively tough.

As a solution to the foregoing problem, it has been proposed to treatthe fruit with various solutions which more or less balance theequilibrium vapor pressures of the fruit and dry cereal components ofthe mixture and thereby inhibit transfer of moisture from the fruit tothe dry cereal when the two components are stored over long periods oftime as a packaged mixture.

Sweetening a ready-to-eat cereal and dried fruit mixture in accordancewith the present invention at least substantially eliminates the needfor pre-treatment of the fruit component in the manner described abovefor the purpose of obtaining desirable fruit texture. When thesweetening solution used in the practice of this invention is applied toa mixture of ready-to-eat cereal and dried fruit in which the cerealcomponent has a moisture content of less than about 3.5% by weight, thedrier, lower water activity cereal component preferentially absorbswater from the solution, increasing its moisture content to anacceptable shelf stable level of less than about 8%. When the dehydratedfruit is raisins, for example, a final cereal moisture content is about6.5% by weight in the packaged product. Accordingly, the process of thepresent invention may be used to simultaneously: (1) sweeten the mixtureof dry cereal and fruit, and (2) adjust the moisture content of the drycereal to a level more nearly that of the fruit, so as to reduce thetendency of moisture to migrate from the dry cereal to the fruitcomponent of the mixture. The present invention thus has economicadvantages as applied to mixtures of dry cereal or fruit in addition tothe benefits noted above in connection with the sweetening of cerealproducts per se. The aqueous sweetening solution may also be separatelyapplied to the dry cereal and the dehydrated fruit in accordance withthe sweetening process of the present invention. The two sweetenedproducts can then be admixed.

The following examples further describe the present invention. Allpercentages, parts or proportions are by weight and all temperatures arein °F. unless otherwise indicated.

EXAMPLE

A sweetening solution was prepared by adding to 1000 grams of water at100° F., 3.0 grams of malic acid, followed by 12.0 grams of aspartamefollowed by 15.0 grams of vanilla powder. The resultant solution was ofrelatively low viscosity and contained no visible undissolved aspartamecrystals. Analysis showed that 95% by weight of the aspartame issolubilized in the aqueous acid.

The sweetening solution thus prepared was applied to 368.0 g of toastedshredded wheat cereal having a moisture content of about 2.5%. An airatomizing nozzle was used to apply the solution at a rate of about 34.0grams per 15 seconds under a pressure of 20 p.s.i.

The sweetened shredded wheat was analyzed by high performance liquidchromatography and was found to have an aspartame content of about0.040% by weight. The sweetening derivative was not visible on thesurface of the product. The sweetened product had a moisture content ofabout 7% by weight. Drying of the product was not required. No "hotspots" were detected when the shredded wheat was eaten in admixture withmilk.

COMPARATIVE EXAMPLE

An aspartame-containing coating composition was prepared in accordancewith the disclosure of U.S. Pat. No. 3,955,000, by adding 1000 grams ofwater at 100° F. to 650 grams of maltodextrin (Amaizo Brand), withstirring to eliminate lumps, and thereafter blending in 12 grams ofaspartame with further stirring for about 5 minutes.

The resultant composition contained approximately 37% by weightundissolved aspartame crystals, and was relatively thick and sticky.

The coating composition was applied to toasted shredded wheat using thesame application procedure and apparatus described in the above Example.The sticky nature of the composition caused periodic clogging of thespray nozzle during application.

The coated product was dried in a Proctor and Swartz oven for 25 minutesat 180° F. and analyzed by high performance liquid chromatography. Theaspartame content of the dried product was about 0.055%. A slight shinycoating was apparent on the surface of the dried product that detractedfrom its natural look. "Hot spots" were detected upon eating the cerealin milk indicating that the coating resists dissolution with aconsequent retention of undesirable localized concentrations of theaspartame.

What is claimed is:
 1. A process for sweetening a dry, baked comestiblewith an L-aspartic acid sweetening derivative, which process comprisesapplying to the baked comestible a sweetening solution comprising waterand at least one L-aspartic acid sweetening derivative, said solutionhaving a pH in the range of from about 1.5 to about 4.0 andsubstantially all of said at least one sweetening derivative beingdissolved in the water, so as to substantially uniformly distribute saidsweetening derivative onto the surface of said comestible and to providea sweetening amount of said sweetening derivative which is absorbedbeneath the surface of said comestible thereby precluding the appearanceof a coating upon the comestible, wherein the moisture content of thebaked comestible before application of said sweetening solution issufficiently low so that application of the sweetening solution raisesthe moisture content to a shelf stable level.
 2. A process as claimed inclaim 1, wherein the moisture content of the baked comestible beforesaid application is from about 0.8% to about 3.5% by weight and afterapplication of said sweetening solution it is less than about 8% byweight of said comestible.
 3. A process as claimed in claim 2, whereinsaid sweetening derivative is N-L-α-aspartyl-L-phenylalanine methylester.
 4. A process as claimed in claim 3, wherein the concentration ofsweetening derivative in the sweetening solution is about 0.03% to about3.5% by weight of said sweetening solution.
 5. A process as claimed inclaim 4, wherein the temperature of the sweetening solution is about 85°F. to about 115° F.
 6. A process as claimed in claim 1, wherein theconcentration of said sweetening derivative and the temperature of saidsweetening solution are insufficient for crystallization of saidsweetening derivative.
 7. A process as claimed in claim 3, wherein saidsweetening solution contains a pharmaceutically acceptable acid formaintaining the pH thereof in the range of about 1.8 to about 2.3.
 8. Aprocess as claimed in claim 7, wherein said pharmaceutically acceptableacid is at least one organic acid.
 9. A process as claimed in claim 8,wherein said organic acid is malic acid or citric acid.
 10. A process asclaimed in claim 3, wherein said sweetening solution includes aflavoring agent.
 11. A process as claimed in claim 10, wherein saidflavoring agent constitutes from about 0.5% to about 2.5% by weight ofsaid sweetening solution.
 12. A process as claimed in claim 11, whereinsaid flavoring agent is vanilla powder.
 13. A process as claimed inclaim 1, wherein said comestible is a ready-to-eat cereal, saidsweetening derivative is N-L-α-aspartyl-phenylalanine methyl ester andits concentration in the sweetening solution is about 0.030% to about3.5% by weight of said sweetening solution.
 14. A process as claimed inclaim 13, wherein said cereal is a shredded cereal.
 15. A process asclaimed in claim 14, wherein said sweetening solution is applied to thebaked comestible in the form of a mist.
 16. A process as claimed inclaim 13, wherein said cereal is a flaked cereal.
 17. A process asclaimed in claim 13, wherein said cereal is mixed with dried fruit. 18.A process as claimed in claim 17, wherein said sweetening solution isalso applied to the dried fruit.
 19. A process as claimed in claim 1,wherein said sweetening solution is applied using an air-pressureassisted spraying means.
 20. A process for sweetening a dry, bakedcomestible with an L-aspartic acid sweetening derivative, which processcomprises applying to the baked comestible a sweetening solutioncomprising water and at least one L-aspartic acid sweetening derivative,said solution having a pH in the range of from about 1.5 to about 4.0,so as to substantially uniformly distribute said sweetening derivativeonto the surface of said comestible and to provide a sweetening amountof said sweetening derivative which is absorbed beneath the surface ofsaid comestible thereby precluding the appearance of a coating upon thecomestible, wherein the moisture content of the baked comestible beforeapplication of said sweetening solution is sufficiently low so thatapplication of the sweetening solution raises the moisture content to ashelf-stable level less than about 8 percent by weight of saidcomestible.
 21. A process for sweetening a dry, baked comestible with anL-aspartic acid sweetening derivative, which process comprises applyingto the baked comestible a sweetening solution comprising water and atleast one L-aspartic acid sweetening derivative, said solution having apH in the range of from about 1.5 to about 4.0 and substantially all ofsaid at least one sweetening derivative being dissolved in the saidwater, wherein the moisture content of the baked comestible beforeapplication of said sweetening solution is sufficiently low so thatapplication of the sweetening solution onto the surface of saidcomestible provides a sweetening amount of said sweetening derivativewhich is absorbed beneath the surface of said comestible therebyprecluding the appearance of a coating upon the comestible, and raisingthe moisture content of the baked comestible to a shelf stable level.22. A process as claimed in claim 21, wherein said sweetening derivativeis N-L-α-aspartyl-L-phenylalanine methyl ester and said sweeteningsolution contains at least one organic acid selected from citric acidand malic acid in an amount effective to maintain the pH of saidsolution in the range of from about 1.8 to about 2.3.
 23. A process asclaimed in claim 21, wherein said sweetening solution contains an amountof a flavoring agent effective to enhance the sweetness of saidsweetening derivative as applied to said comestible and to at leastpartially mask any unpleasant aftertaste associated with said sweeteningderivative.
 24. A process for sweetening a ready-to-eat cereal admixedwith dried fruit with an L-aspartic acid sweetening derivative, whichprocess comprises applying to said cereal and said fruit a sweeteningsolution comprising water and at least one L-aspartic acid sweeteningderivative, said solution have a pH in the range of from 1.5 to about4.0 and substantially all of said at least one sweetening derivativebeing dissolved in the water, so as to substantially uniformlydistribute said sweetening derivative onto the surfaces of said cerealand said fruit and to provide sweetening amounts of said sweeteningderivative which are absorbed beneath the surfaces of said cereal andsaid fruit thereby precluding the appearance of coatings upon saidcereal or said fruit, wherein the moisture content of said cereal andsaid fruit before applying said sweetening solution are such thatapplying the sweetening solution produces moisture contents in saidcereal and said fruit which provide a shelf stable product, and whereinthe moisture content of said cereal is increased to a level more nearlythat of said fruit, to minimize the migration of moisture to said cerealfrom said fruit.
 25. A process as claimed in claim 24 wherein saidsweetening solution is applied to said cereal in admixture with saidfruit.
 26. A process as claimed in claim 24 wherein said sweeteningsolution is applied to said cereal and said fruit separately.
 27. Aprocess for sweetening a dry, baked comestible with an L-aspartic acidsweetening derivative, which process comprises applying to the bakedcomestible a sweetening solution comprising water, at least oneL-aspartic acid sweetening derivative and a flavoring agent comprising avanilla flavor, said solution having a pH in the range of from about 1.5to about 4.0, so as to substantially uniformly distribute saidsweetening derivative onto the surface of said comestible and to providea sweetening amount of said sweetening derivative which is absorbedbeneath the surface of said comestible thereby precluding the appearanceof a coating upon the comestible.